| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | /* | ||
| 2 | * This file is part of FFmpeg. | ||
| 3 | * | ||
| 4 | * FFmpeg is free software; you can redistribute it and/or | ||
| 5 | * modify it under the terms of the GNU Lesser General Public | ||
| 6 | * License as published by the Free Software Foundation; either | ||
| 7 | * version 2.1 of the License, or (at your option) any later version. | ||
| 8 | * | ||
| 9 | * FFmpeg is distributed in the hope that it will be useful, | ||
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
| 12 | * Lesser General Public License for more details. | ||
| 13 | * | ||
| 14 | * You should have received a copy of the GNU Lesser General Public | ||
| 15 | * License along with FFmpeg; if not, write to the Free Software | ||
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
| 17 | */ | ||
| 18 | |||
| 19 | /** | ||
| 20 | * @file | ||
| 21 | * EVC decoder/parser shared code | ||
| 22 | */ | ||
| 23 | |||
| 24 | #ifndef AVCODEC_EVC_PARSE_H | ||
| 25 | #define AVCODEC_EVC_PARSE_H | ||
| 26 | |||
| 27 | #include <stdint.h> | ||
| 28 | |||
| 29 | #include "libavutil/intreadwrite.h" | ||
| 30 | #include "libavutil/log.h" | ||
| 31 | #include "evc.h" | ||
| 32 | #include "evc_ps.h" | ||
| 33 | |||
| 34 | // The sturcture reflects Slice Header RBSP(raw byte sequence payload) layout | ||
| 35 | // @see ISO_IEC_23094-1 section 7.3.2.6 | ||
| 36 | // | ||
| 37 | // The following descriptors specify the parsing process of each element | ||
| 38 | // u(n) - unsigned integer using n bits | ||
| 39 | // ue(v) - unsigned integer 0-th order Exp_Golomb-coded syntax element with the left bit first | ||
| 40 | // u(n) - unsigned integer using n bits. | ||
| 41 | // When n is "v" in the syntax table, the number of bits varies in a manner dependent on the value of other syntax elements. | ||
| 42 | typedef struct EVCParserSliceHeader { | ||
| 43 | uint8_t slice_pic_parameter_set_id; // ue(v) | ||
| 44 | uint8_t single_tile_in_slice_flag; // u(1) | ||
| 45 | uint8_t first_tile_id; // u(v) | ||
| 46 | uint8_t arbitrary_slice_flag; // u(1) | ||
| 47 | uint8_t last_tile_id; // u(v) | ||
| 48 | uint32_t num_remaining_tiles_in_slice_minus1; // ue(v) | ||
| 49 | uint16_t delta_tile_id_minus1[EVC_MAX_TILE_ROWS * EVC_MAX_TILE_COLUMNS]; // ue(v) | ||
| 50 | |||
| 51 | uint8_t slice_type; // ue(v) | ||
| 52 | uint8_t no_output_of_prior_pics_flag; // u(1) | ||
| 53 | uint8_t mmvd_group_enable_flag; // u(1) | ||
| 54 | uint8_t slice_alf_enabled_flag; // u(1) | ||
| 55 | |||
| 56 | uint8_t slice_alf_luma_aps_id; // u(5) | ||
| 57 | uint8_t slice_alf_map_flag; // u(1) | ||
| 58 | uint8_t slice_alf_chroma_idc; // u(2) | ||
| 59 | uint8_t slice_alf_chroma_aps_id; // u(5) | ||
| 60 | uint8_t slice_alf_chroma_map_flag; // u(1) | ||
| 61 | uint8_t slice_alf_chroma2_aps_id; // u(5) | ||
| 62 | uint8_t slice_alf_chroma2_map_flag; // u(1) | ||
| 63 | uint16_t slice_pic_order_cnt_lsb; // u(v) | ||
| 64 | |||
| 65 | // @note | ||
| 66 | // Currently the structure does not reflect the entire Slice Header RBSP layout. | ||
| 67 | // It contains only the fields that are necessary to read from the NAL unit all the values | ||
| 68 | // necessary for the correct initialization of the AVCodecContext structure. | ||
| 69 | |||
| 70 | // @note | ||
| 71 | // If necessary, add the missing fields to the structure to reflect | ||
| 72 | // the contents of the entire NAL unit of the SPS type | ||
| 73 | |||
| 74 | } EVCParserSliceHeader; | ||
| 75 | |||
| 76 | // picture order count of the current picture | ||
| 77 | typedef struct EVCParserPoc { | ||
| 78 | int PicOrderCntVal; // current picture order count value | ||
| 79 | int prevPicOrderCntVal; // the picture order count of the previous Tid0 picture | ||
| 80 | int DocOffset; // the decoding order count of the previous picture | ||
| 81 | } EVCParserPoc; | ||
| 82 | |||
| 83 | 606 | static inline uint32_t evc_read_nal_unit_length(const uint8_t *bits, int bits_size, void *logctx) | |
| 84 | { | ||
| 85 | 606 | uint32_t nalu_len = 0; | |
| 86 | |||
| 87 |
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606 | if (bits_size < EVC_NALU_LENGTH_PREFIX_SIZE) { |
| 88 | ✗ | av_log(logctx, AV_LOG_ERROR, "Can't read NAL unit length\n"); | |
| 89 | ✗ | return 0; | |
| 90 | } | ||
| 91 | |||
| 92 | 606 | nalu_len = AV_RB32(bits); | |
| 93 | |||
| 94 | 606 | return nalu_len; | |
| 95 | } | ||
| 96 | |||
| 97 | int ff_evc_parse_slice_header(GetBitContext *gb, EVCParserSliceHeader *sh, | ||
| 98 | const EVCParamSets *ps, enum EVCNALUnitType nalu_type); | ||
| 99 | |||
| 100 | // POC (picture order count of the current picture) derivation | ||
| 101 | // @see ISO/IEC 23094-1:2020(E) 8.3.1 Decoding process for picture order count | ||
| 102 | int ff_evc_derive_poc(const EVCParamSets *ps, const EVCParserSliceHeader *sh, | ||
| 103 | EVCParserPoc *poc, enum EVCNALUnitType nalu_type, int tid); | ||
| 104 | |||
| 105 | #endif /* AVCODEC_EVC_PARSE_H */ | ||
| 106 |